1. Technical Field
The present invention is directed to optical information readers and more particularly to readers adapted to selectively decode two-dimensional optical information sets.
2. Description of the Prior Art
Conventional bar code symbols have small data storage capacities. This reduces the utility of conventional bar code scanner and reader systems. For example, the 11 digit Uniform Pricing Code found on most supermarket items acts as an identifying number which may be utilized to access information in a database. Codes of this type do not carry information along their vertical axis, and are therefore, less prone to skewing errors during decoding.
Two-dimensional bar code symbols or "portable data files" have recently been developed. With codes of this type access to a database is not required since the code contains the information which would normally be keyed for in a database. Since database reliance on a database is not required, information may be accessed and exchanged more readily and reliably. However, in order to decode two-dimensional codes a more sophisticated apparatus is required. This is primarily true since normal vertical code redundancy is not present, making code registration, orientation, and condition very important.
Several two-dimensional coding standards have been proposed, e.g., Code 49, 16K, Identicode MLC-2D, and Code PDF417. While such codes are capable of storing information such as price, name of product, manufacturer, weight, expiration date, inventory data, shipping information, and the like; apparatus which assist the user in aiming and decoding two-dimensional codes are not currently available.
For example, two dimensional codes might consist of a stack of conventional linear codes. The first line might contain pricing information, the second the product name, the third name of the manufacturer, and successive lines might contain product weight, expiration date, inventory data, shipping information, and the like. Additionally, a user may require the ability to selectively send portions of the decoded bar code symbol.